Slide fastener



Dec. 23, 1941. J. BROZEK SLIDE FASTENER Filed Aug. 9, 1940 WITNESS 5??? ATTORNEYS Patented Dec. 23, 1941.

UNITED STATES PATENT OFFICE SLIDE FASTENER Joseph Brozek, Jackson Heights, N. Y., assignor to Waldes Koh-I-Noor, Inc Long Island City, N. Y., a corporation of New York Application August 9, 1940, Serial No. 351,940

r 4 Claims. 24205) This invention relates to the manufacture of separable fasteners of the slide-operated type. A fastener of this type usually comprises a pair of stringers or tapes having reenforced opposed edges to which the interlocking fastener elements are attached in closely spaced relation by means of suitable clamping jaws. The edge of a stringer may be reenforced in various ways, i.-e., by sewing one or'two cords to one or both sides, respectively, of the longitudinal edge portion of the stringer; by weaving or braiding a twisted cord in the edge of the stringer when it is manufactured; or by folding the edge of the stringer or tape about the cord and applying a longi-' tudinal line of stitches adjacent to the cord inwardlyof the folded edge of the tape or through the cord and tape or depending upon the clamping jaws of the interlocking elements to hold the cord and tape together.

As is well known to those skilled in the art, the clamping or clinching of the fastener elements to the reenforced edges of the stringer tapes causes the tapes to lose their straight flat shape and to assume a curved shape in which .the reenforced edges areconvexly curved while the opposite edges are concave. This condition.

stringer tapes in which the cord is woven and in which the cord is merely enclosed by a line of stitches. The result is that when the ,tapes are secured to a garment or the like, the reenforced edges thereof to which the elements are attached assume"a wavy or rippled condition which is highly objectionable because it destroys the neat appearance of the fastener, causes unsightly bulging 0r puckering of the garment material to which the tapes are attached and restricts the free movement of the/slider along the rows ofelements.

In an attempt to remedy. the foregoing disadvantages the art has tried various methods of combining the stringer with the reenforcing cord and the fastener elements but such known methods, so far as applicant is aware, have never succeeded in completely eliminating the undeaccordingly in addition to such methods of com bining these parts, has adopted the practice of washing the stringers after the fastener elements have been attached, then stretching the stringers to make both longitudinal edges thereof as ing them. There is then provided to the customer an article which is free of the disadvantages previously mentioned but as soon as the stringers of a fastener are washed with the garment to which they are attached, the stringers again assume the condition in which they were before being subjected to the stretching and starching procedure,

The object of the present invention is to provide an improved method of manufacturing fastener stringerswhich will overcome the dimculties above mentioned and will provide an improved product which has special advantages over prior constructions as will hereinafter become more apparent. V

In the accompanying drawing Fig. 1 illustrates a portion of a stringer tape in the process of being constructed according to the teachings of this invention; Fig. 2 is a view similar to Fig. 1 but showing a different method of stitching the cord to the tape; Fig. 3 is a sectional view of a completed stringer tape showing the relationship of the parts; Fig. 4 is a view similar to Fig. 3

illustrating a modified form of the invention,

and Fig. 5 is a view similar to Fig. 3 and showing the tape and cord assembly before the elements are clamped in position thereon, one of the elements being shown in dotted outline. I

In the drawing, in which similar reference characters indicate similar parts throughout the several views, the numeral l0 refers to a base strip or stringer tape upon which the fastener elements H are attached. Extending along one side edge of the tape III is a cord l2 which prefsirable results previously mentioned. The art erably is made of cotton and composed offive coiled strands with each strand composed of three The tape I0 is folded back. along such edge around the co'rdiI, the folded coiled threads.

the tape beyond the intumed edge of the folded portion l3 thereof. Extending lengthwise of the tape is a line of stitches which extend through the tape II, the cord l2 and the folded portion l3 of the tape. The stitches penetrate the folded portion l3 adjacent the longitudinal free edge thereof and penetrate the cord I! along a line substantially offset from the axial center of the cord, as can be seen more clearly from Fig. 5 of the drawing. The stitches are preferably so positioned that they just catch the inner longitudinal edge portion of the cord and in the unclamped condition of such parts are wholly contained in a region intermediate horizontal planes tangential to the outer surface of the folded portion l3 and to the under surface of the body portion of the tape underlying the cord and normal to a vertical plane passed through the axial center of the cord. For the construction illustrated in Fig. 1, the line of stitches are designated l5 and are of a zig-zag nature, one end of each of the stitches extending through the tape l0 only at a point adjacent to the edge of the folded portion l3 while the other end of the stitch penetrates through the tape III, the folded portion l3 and the cord II. In the construction illustrated in Fig. 2 of the drawing, the line of stitches designated I6 is composed of straight stitches extending longitudinally of the cord and penetrating both the cord II, the tape l0 and the folded portion l3 thereof.

In making the stringers above described, the tape I0 is progressively folded along one edge about the cord II, as is indicated in Figs. 1 and 2 of the drawing. The fold as has been previously mentioned is only suflicient to enclose the cord l2 so that when the line of stitches are applied the free edgeof the folded portion I: of the tape and the stitched side of the cord will be substantially in alignment. At the same time that the edge of the tape is being folded. the longitudinal line of stitches are progressively applied so that as soon as a portion of the tape is folded over the cord, the latter together with the tape and folded portion thereof are secured together. During this operation the tape and the v cord are fed while under tension, the tension on the cord however being substantially greater than that on the tape it. Thus after the sewing operation, the tape will, due to the increased tension of the cord, assume a radial form, the beaded edge of the tape being the shorter side and concaved in form. The tape as thus formed is then fed to a machine where the fastener elements I I are progressively clamped into position on the tape, the crushing action exerted by the jaws ll of the elements causing the tape to elongate on the cord side and causing the radial form of the tape to assume a straight form.

As a result of the foregoing it will be observed that the cord is caught and fixedly secured in position with relation to the tape at the same time that the short flap or folded portion I 3 is stitched in position and in this way it is prevented from moving relative to the tape when subjected to the combing action of the tools applying the fastener elements and the crushing action of the clamping jaws of such elements.

In view of the fact that the folded portion l3 does not extend beyond the inner ends of the jaws of the fastener elements, such portion when the elements are clamped in position will not be visible, as isclearly shown in Figs. 1 and 2 of the drawing. Consequently, the tape has the appearance of a single tape and not of a tape with an extended flap. By reason of this construction also, the longitudinal free edge of the folded portion I3 is fixedly clamped in position so that it will not turn up in usage to present an unsatisfactory appearance and will not interfere with the operation of the slider whose inturned flanges engage the inner ends of the jaws of the fastener elements. Furthermore by having the longitudinal line of stitching just catching the inner side of the cord there is prevented any danger of the clamping jaws of the elements cutting through the stitches when the elements are being applied to the corded edge of the tape. This method of stitching is also of advantage where the folded portion is made sufiiciently wide to enable it 'to be reversely folded over the clamping jaws of the elements as is indicated by the folded portion designated 11 in Fig. 4 of the drawing. When the line of stitching extends through the center of the cord or when it is lies adjacent to the cord without penetrating the same, the reverse fold of the cover portion forms a poor shoulder due to the fact that a so-called air gap is formed between the cover portion and the inner ends of the clamping jaws of the elements and due to the fact that the regularity and evenness of the portion overlying the elements cannot be controlled. With applicants method however, a sharply defined shoulder is provided, the cloth of the folded portion snugly and tightly enclosing the clamping jaws of locking elements without any intermediate air gap or looseness and being capable of being laid evenly and regularly over such clamping jaws, whereby a ridge or track is formed which will facilitate the operation of the slider thereover. The covering portion I1 is maintained in this condition by a longitudinal line of stitches which are designated l8 in Fig.

4 of the drawing, and which securely fasten the covering portion H to the upper surfaces 0 the elements ll.

While I have in this application described and illustrated specific preferred embodiments which my invention may assume in practice, it will be understood that various changes and modifications thereof may be made without departing from the scope of the invention as defined in the appended claims.

I claim:

1. In a fastener structure of the slide-operated type, a flexible supporting strip folded along a longitudinal edge to provide a turned back folded portion, a strengthening cord extending longitudinally of the strip and being positioned intermediate the body of said strip and said folded portion and against the interior surfaces of the foldformed along the longitudinal edge of the body of the strip so as to be enclosed between said folded portion and the longitudinal edge portion of the body of the strip, a line of stitches penetrating said folded portion, cord and body of the strip and permanently securing the same together, said line of stitches being offset from the axial center of said cord and penetrating said cord closely adjacent to the longitudinal edge thereof which is diametrically opposite the fold of said strip so that said line of stitches just catchesthe inner longitudinal edge portion of the cord and in the unclamped condition of said cord are wholly contained in a region having a width less than the space intermediate horizontal planes parallelly disposed to the body of the strip, tangential to the upper and lower surfaces of the portions of the strip enclosing said cord and normal to a vertical plane passed through the axial center of the cord, and a iOW 0f fastener elements having clamping Jews clinched to said reenforced edge of said strip 2; fastener'strueture such as set forthin claimiinwhic'hsaidfoldedportionhasawidth less than the lengthot the clamping iaws-of the fastener element and in which the line 01 sewin! is composed of sis-mg stitches, one end of each of'saidi stitches penetrating the body portion and folded portion of said strip and the cord and the "other of said stitches penetratingjthe body portion only of said strip.

8. A fastener structure such as set forth in claim '1 in which said folded portion has a width less than the length of the clamping laws of the fastener elements whereby said tape has the appearance of a single tape and said folded portion will notinterfere with the operation of the slider during usage. a

4. In a fastener structure of the slide-operated type, a flexible supporting strip folded alons a longitudinal edge to provide a turned-back folded portion. a cord extending longitudinally. of the strip and being positioned intermediate the body of said strip and said iolded portion and against the interior surfaces of the fold connecting said folded portion with the longitudinal edge portion of the body oi the strip, said folded portion having a width such that'the cord is just enclosed by said turnedback ioided portion, a line of stitches penetrating said folded portion, cord and body of I the strip and permanently securing the same together, said line of stitches extending longitudinally of thesupporting strip, penetrating said iolded' portion along the free edge thereof and penetrating the inner longitudinal edge of the cord underlying the free edge of the folded por- J n'reozax. 

